In the conventional X-Y travelling table, a pair of monoaxial moving mechanisms, each of which is composed of a pair of straight motion guide bearings and one feed screw mechanism for causing movement in one direction, are superposed with their moving directions being orthogonal to cause a table to move lengthwise and crosswise thereof. When such a mechanism has a table turning mechanism added to this X-Y moving mechanism, this causes various problems, such as that the height from the support base to the table is so great as to make the mechanism relatively unstable and to cause it to occupy a large space, that the number of parts is large, that many man hours are required for assembling, that it is relatively difficult to assemble accurately, and so on.